R ESTR IC rED

Report No. TO- 33IAb

This report was prepared for use within the Bank and its affiliated organizations.They do not accept responsibility for its accuracy or completeness. The report mayI not be! published nor may it be quoted as representing their views.

INTERNATIONAL BANK FOR RECONSTRUCTION AND DEVELOPMENT

INTERNATIONAL DEVELOPMENT ASSOCIATION

BRAHMAPUTRA FLOOD EM:BANKMENT PROJECT

EAST PAKI:STAN

Tune 17 i1a96

Department of Tec:hnical Operations

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CURRENCY EQUIVALENTS

4.762 rupees U.S. $1. 001 rupee U.S. $0. 21I million rupees - IJ. S. $210, 000

WEIGHTS

I! -.an -37. g. or 8 2. 3 lOb.

BAPMA PTTP A FLTnnTD IRMPA1W1vT-NT PpOJECT

TABLE OF CONTENTS

Pages

SUNMARY

I. INTRODUCTION 1

II. BACKGROUND INFORIATION 1

III.THE PROJU3CT AREA

A. Location 2B. ClimateC. Topography and Soils 2D. Farm Size and Land lenureE. Acreages 3F. Floods and Drainage 3G. Present Cropping Pattern and Yields 4H. Marketing and IransportationiI. Gross and Net Value of Present Production 5

IV. THE PROJECT

A. General 6B. The Proposed Works 6C. Construction Schedule 7D. Cost Estimates 8E. Finance 9F. Organization and Management 10G. Operating Results 11

V. BENEFITS AND JUSTIFICATIOIJ 12

VI. CONCLUSIONS AND RECOMNLENDATIONS 13

ANNEXES:1. Present Cropping,Yields, Pr:ices and Value of Production2. Types of Rice Grown in the Area3. Approximate Farm Budgets "Before"' and "After" Project

for Farms with 5.8 Cultivated Acres4. Construction Schedule5. Cost, Estimate6. i'JnEncial (reratinn ;.etu1t at. Full leveloPnmnt.7. Future Cropping, Yields, Pr:ices and Value of Production

TABLE OF CONTENTS

*2.-

ANNEXES:8. Surrmiarv of Gross and Net Value of Production before

and after Project9; heSPription of Proposed Works

i5A P

P A K I IS T A N

BRA_WiAPUTRA FLOOD EPHBA.DaiENT PROJECT

S U M M A RY

i. The Government of Pakistan has requested a development credit fromthe International Development Associaticon to help finance a flood embankmentproject on the right banks of the Teesta and Brahmaputra Rivers in EastPakistan.

ii. The purpose of the project is to afford flood protection to a grossarea of 593,500 acres, of which 39h,000 acres are estimated to be undercultivation. The project involves the construction of an earth embankment135 miles long with 8 regulators.

iii. Preliminary project design has been undertaken on behalf of theEast Pakistan Vater and Power Development Authority (EP.VAPDA) by its generalconsultants, International Engineering Company. Construction of the workswould be spread over three years. EP.IKAPDA would be responsible for theexecution of the project, assisted by experienced foreign consultants.

iv. The total cost of the project, including interest during construc-tion, is estimated at Rs. )h6.7 million of which Rs. 8.0 million would beforeign exchange. The IDA credit sought wjould be US25 million, equivalentto about 50 per cent of the total cost cof the project. The Government ofPakistan would relend the credit to the Province of East Pakistan on thesame terms and conditions as those agreed upon between IDA and the Governmentof Pakistan.

V. Protection from flooding would ernable the numerous small farmersin the project area, using the same crops as at present, to adopt a moreprofitable cropping pattern and, by avoidance of losses due to flooding, toobtain higher yields. The net farm benefit/investment ratio, after allowingfor a five-year development period and cliscounting the annual benefits overthe lifetime of the project (50 years) is estimated at about 50 per cent.

vi. The technical aspects of the project are sound and economic benefitswould be substantial. The Droject wJould be suitable for an IDA credit ofUSQ5 million.

D A LI T C' m A 1U1 <. IX. E. ,, 4. ~ti I

_17 A TTA A rTTRn AFL O .r - 'I,AT IMT PTOX TT'MDLflPAZU- U IEl,-' P 'LJkU%JLIiAr I -J IftUU , I

I. INxTRODUiCTION

1. The Government of Pakistan has requested a development creditfrom !DA to help finance a i±ood embankment project located on the rightbanks of the Teesta and Brahmaputra Rivers in East Pakistan. The projectinvolves the construction of an e--rt.h embanKment 135 miles long with eightregulators and is designed. to afford. flDod protection to a gross area of593,500 acre,, of whiych 394,000 acres (k6 per cent) are estimated to beunder cultivation.

2. A field mission investigated the project in Earch/April 1962 andthis appraisal report; is based on the findings of the mission and on inform-ation supplied by the authorities in. East ]akistan. Much of the informationsupplied to the mission was contained in a report prepared for the EastPakistan Water and Power Development Authority (EP.I/WAPDA) byr its engineeringconsultants, International Engineering Co., who prepared preliminary designsfor the project. The estimated total cost of the project is Rs. 46.7 million.The amount o.' an IDA credit to provide .approximately 50 per cent of the costof the project would amount to US$5 mil:Lion.

II. BACKGROUND rNF'ORMATION

3. The economy of East Pakistan :is predominantly agricultural, butconsiderable quantities of food have had to be imported in recent years.There is an urgent need to increase domestic food production to keep pa.cewith the demands of a rapidly increasing population and to reduce importsof food grains. The pressure of population is severe; East Pakistan hasa cultivated area of about 22 million acres and a present population ofover 50 million. The problem is to incre?se production from the existingcultivated area.

4. Past Pakistan has some considerable natural advantages, includingfertile alluvial soil and suitable temperatures for crop growing throughoutthe year. Rainfall is high but is badly distributed and this makes cropproduction uncertain. The key to increased production is control of waterby preventiorn of flooding and by provision of irrigation. At present, partsof the cultivated area are flooded d:urinig the monsoon season and much of thearea suffers from drought during the winter months.

ITT. THE PROJECT AREA

A. Lcocation

5. The project area (see map) is located in the districts ofPu gurT og- ar.d F-4-n ,-.4. T+ A is ii"Aaer lon +.'he north

by the Teesta River, on the east by the Brahmaputra River, on the south

Railway and a high ridge of land betwleen Bogra and Ullapara,

B. Clirate

6. The project area experiences a subtropical climate of the monsoontype. riean armnual urdr-prTIX-1ur- -X l --t-UJe area iaOU 1o "A ergrees.Maximm temperatures occur in April (average daily maximum about 96 degrees),-with mean r i-ini untl emperat-ures Xi Janluary (aera'g ' about3 '-"rT

peratures are always within the range suitable for crop growth and givencontrolled water, culti-vation would be possible throu-ighout the year. Tlleaverage annual rainfall over the project area varies from 86 inches inwthe nlUI-ort h Ut inlches uon lthe soU1Athrn U slUdar-y. AboUUt UU pu- cent of U te

average annual precipitation occurs during the monsoon season from Maythrough September with consistently heavy- falls in t*he period Jiule toSeptember (up to 45 inches in a single month). During the dry seasonthere may be some monthns with no rainfall.

C. Topographny an Soiis

7. Lne project area forms part of the vast delta of the Ganges-Brahmaputra Rivers. It is a gently sloping alluvial plain which variesin elevation from about 100 feet above sea level in the north to about 35feet in the south. The general slope below Pulchari is to the southwest.From Sirajganj to the junction of the Karatoa-Hurasagar and Brahmaputrarivers the land slopes in a southerly direction at a much flatter gradientthan the land to the north.

8. The project area is part of the new alluvium of the Teesta andBrahmaputra Rivers. Tho soils are typically stratified, with the upperlayers being generally finer textured than the deeper layers. Dominantsurface textures range from fine sandy loam to silty clay loam, with ahigh proportion of soils having a loam or silt loam texture. Soils inthe project area have a high moisture content with only small quantitiesof organic materials. Except in local depressions, the soils are fairlywell drained when not inundated; they are well supplied with potash andphosphate, writh pH ranging from 6 to 6,5, and respond to applications ofnitrogen and phosphatic fertilizers. Soil analysis shows that the saltcontent is extremely low. Cropping lirmitations are imposed more by flood-ing and drought than by soil type.

D. Farm Size and Land Tenure

9. The population in the area avrerages about 1,030 persons per squaremile. The average farm in the project area is estimated to be about 6.2

acres of which 5.8 acres are cultivateel. This size is above the averageof East Pakistan- According to a survevy 9 rpr cent of the farms in theproject area. are smaller than 2 acres End 7 per cent larger than 10 acres.The fnarms are fra-men+.ted. Aordrin tr thep Enast. RP-noal T.anrl Ac.rnniTitionand Tenancy Act of 1950, the Government is theoretically the sole land-ownrer, +tking land tax (rent) directly from the occupying farmers (tenants)IThis nominal.ly exclusive ownership by the state has little practical effecton the position of the occupancy +na-+o since the tenan,y is hrtb andtransferable at its market price by sale. Thus, the farmers' rights tothe land are virtually those of oPM.ershipf. 11"n"+tf "et A Ain the for. of

land tax averages around Rs. 6.0 per acre per annum in the project area,

E. Acreages

10. The project area can be divi(led into three divisions. Division.LI, or T~eestca Divisic;n, c ov-,e rsLL1 the I. nortlf.L ar from Kauinia .Raiblway BIndt.CEe~~± ±~~O UCL V~~~L'~)LI, A A~L~ A~ FL . U L.± JAl U LJ t

over the Teesta to t;hat river's confluence! irith the Brahmaputra near Belka.Di-rision II., to the south of Division ]:, in.cludes the land behin.d an em.-bankment bui.lt from Belka to Pulchari (about 24 miles in length) in 1957.Di-v-ision I.I.. iLrlcLUdes e larget, souI4eJrnmos tu paru oL Wle proJecu area LL-cm

Pulchari to Sirajganj.

11. The gross area of 593,500 acres is divided between the threedivisions as follows;:

Divnsion uross Cuiliivated Land Percent1Acres Acres of Gross Area

Di.1.v Ji.ion I 7v30 , lvT9004 70 fn&.nn~ l

IJLV±.Ls-IonI 3 U±,UUL :?'8U2,006

- Tr L'1.~ 4Af\ )Pe A/V UL V _ .I. JAJJ L_L.L 4.l.J. v4 Vr ,,,U1 ULp U_~

Total 593 ,500 393,700 66

12. The lands which are not under cultivation are used for homestecads,tanks and roads, or occupied by rivers and bils (lakes).

F. Floods and Drainage

13, Many factors combine to limit food production to the present lowlevel; amongst the most obstinate are those inposed by tne alternating floodsand drought, Flooding occurs every year on the lower reaches of the proIect

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as a result of the Brahmaputra River overf:lowing its bank but. not as oftenalong the Teesta River at the upper end of the project area= '!here floodingoccurs regularly, cropping is restricted in the main to the most uncertainand least praducti ,Ve 1 ors of paddy cul-ure.

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14.W Flood peak:; occur twice a year, e in the June-July and August-September periods, and are caused by melting snow in the Himalaya mountainscoincAlding .iL L-I mhr,onsoon raidnf1a1ll in the BrahmL,aputra and Teesta River basi-s.

Flood water coming from sources other than these two rivers is derived fromthe b)aslns ofr thLe smlll internal streacms and 'ls limited in vol umIe.

15. SotL-h of Pulchari, in Division IIi, the Drahmaputra River bankis relatively low and there is widespraad overbank flooding of annual occurr-ence during the high stages of the river. Damage to crops is caused not onlyby inundation, but also by the force of the flood currents. On two occasionsrecently (1954 and 1958) overbank flood:ing has been continuous for threemonths withouat interrmission.

G. Present Cropping Pattern and Yields

16. Details of the present cropping and yields are given in Annex i.The estimates of acreages and yields are based on sample agri.culturalsurveys of the project area, supplemented by official statistics and bydata obtained from local union (village) officials.

17. Present cropping patterns difCer in each of the three divisionsas a direct result of the difference in the flood hazard and the depth ofinundation. The main kinds of paddy grown in the area are described inAnnex 2. The percentage of broadcast aman (which is a relatively low yield-ing type of paddy) gi.ves some indication of flood damage because riceproduction is limitecd to this type of rice where inundation exceeds 2.5feet during the growing season. In DivLsion I, where damaging floods donot occur every year in the entire reach, the percentage of ciultivated land.devoted to broadcast aman is negligible; in Division II, affected by damagingflood water from the Brahmaputra River through openings in the existingembankment, the corresponding figure is 12 rer cent; but it is 40 per cent,in Division XII due to the greater depth of flooding.

18. In Divisiori III the percentage of land devoted to aus rice ishigher than in Divisions I and II. The farmers in Division III often mixthis crop with b roadcast aman. A mixture of aus and aman is well adaptedto moderate ilooding and it reduces the risk of loss because at least theaman may produce a crop if floods damage the aus.

19. If it were not for fear of flooding, the farmers would grow moretransplanted aman, which ;'ives relative:Ly high yields, and less broadcast

aman but trarnsplanted aman cannot vithstand flooding to a depth much inexcess of one f oot. JTute 21so suif f ers damape from excessive flooding andthe percentage of lard used for jute in Division III (,ihich is regularlysubjiet to flooiding) is only 21 as comparecl vrith 3h in Division I.

20. AUE. or jute follow^Ied by transplanrted Aman is the main cropsequence in Dlivision I. In Division III the main crop sequence is mixedbroadcast Aus and Aman foilored h,y nplse-s and ilsr5s! nother crop sequen-ces in Division III are Aus or jute fol:Lowed by oilseeds or vegetables.

21. Average yields in the project area are very low. They are high-es -r, D;iso II beh the existir.g embarler.t wh4-ere there i9 -nlrearl-i

some degree of protection from flooding. Yields in Division III aremiarkely A 'ow3e.r than inr- Tiiin -A ar,d:[. This_; is + he result of h,-av kedJ Z.XUly l.UW;J. ULid M, L UVI.J.LWAD .L C~I3.. .L.L* ~ .A ' ., '

flood damage to the main crops (rice, jute and pulses); losses estimatedat up to 80 per cen4t were suffered in parts of the area dur.g +he years1958 to 1960.,

22. Farning methods and equipment are primitive. Very little com-mercial fertilizer iEi used at present" a:Lthough bhe quantities purchasedand mainly applied to cash crops and vegetables are increasing.

H. Marketing and Transportation

23. i4ost of the rice produced in the project area is consumedlocally. The most important cash crop :is jute, which is sent to collect-ing and shipping centers from where it is shipped to the mills * In addi-tion the farmrrers sell small amounts of vegetables, chillies, pulses andoilseeds in local markets or to dealers. Any surplus agriculturalproducts find a ready market at Bogra. A sugar mill of the Pakistan In-dustrial Development Corporation is locatecd at iMahiganj (Rangpur), butreceives only a small amount of sugar cane from the project area becauselittle cane is grown in the area and most of it is used for making gur.

244. Transportation is principally by bullock cart. A motor roadborders most of the area on the West. :Wocal interior roads are suitableonly for bullock carts and are generally in bad condition. A railroadborders the area on the West and South.

I. Gross and Net Value of Present Production

250 Annex 1 gives details of estimated gross value of present pro-duction baseci on sample surveys carried out; by International EngineeringCompany, on official production and price statistics and on observationsby the Mission. The Government guarantees a minimum price of Rs. 12 permaund of padcly but only a very small quantity is sold by the farmersunder these terms and the average annua:L price of medium quality paddyon the free market from 1955/56 to 19590/60 was nearer Rs. 16 per maund;a figure of Rs. IL per maund has been used in Annex 1. The estimatedjute price is Rs. 25 per maund, which was the average annual price ofuhite lute atid in the interior village markets in East Pakistan from

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1955/56 to 1959/60. Estimated price of pulses, Rs. 1l per maund, accordswith the annual average prices from 1956/57 to 1960/61 for the main typesof pulses (weighted average) grown in the project area. The value ofsupar cnne has been based on the ar.TersI minim.um price fixed by theGovernment for the season 1961/62 - ts. 2 per maund.

26. Farn budgets for farms of' average size have been prepared, in-nlui-rir an ,-r..rnn+…e.…n of the fq…0-rrs h Pynses These budgets;shoving the approximate gross and net; values of production, are given inAnnex 3. The present gross value of prcduiction is low, espeiall- ninDivision III. This is mainly the result of the limitations imposed bythe flood condition-s. Cost of production does not -- clude t+he talue of'the farmers' own and family labor.

IV. THE PROJECT

A . G eniera."l

::2 7 1Ce objectlive 01 t'ne pIrJCect i.s o pLevenfl U'arnage 'A)o agricul-tural crops which has been caused in the project area by flood watersfrom tihe Teesta and Brahmaputra Rivers. The embankmenlt project is re-garded as a self-contained unit and can be justified on its own merits;but it is expected that irrigation development of the area will followin due course and WfTAPDA has already had preliminary studies made for this.

B. The Proposed Wviorks

28. The main works would include an earthen embankment 135 mileslong and eight regulators, two for d:ischarge of internal drainage waterand six for controlled intake of flood water. About 24 miles of embank-ment have already been built in Divisiorn II of the project area; thiswork was done in 1957 by the Irrigation Department,whose duties havesince been taken over by EP.WAPDA,but it is inadequate with regard toheight and section, the side slopes beirg too steep, and the necessaryreconstruction is included in the project plan.

29. The average height of the embankment would be about 12 feet,the top width. would be 14 feet in the two upper Divisions (I and II) and24 feet in the lower Division (III). The side slopes would be threehorizontal to one vertical. The top level of the proposed embankment isdesigned to be 5 feet higher than the nr.ximum flood level estimated forfloods of an incidence of one in 100 years.

30. Twyc' regulators would be provided to pass out internal drainagewaters from Divisions I and II; they would be gated to prevent ingressof flood vaters from the Brahmaputra. Along the embankment in DivisionIII, six regulators would be provided to enable controlled amounts offlood water to be brought from the Brahmaputra into the project area.Internal drainage in Division III would be directed into existing chan-nels to the South.

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31. The preliminary designs prepared for the project by the Inter-national Engineer4ng G.mpany are considered. adequate at this stage forthe purposes of estimating. Further site tborings need to be undertakenhefore the 1rrcations of' the regulaters r drterrntnex1. Details of theproposed works are given in Annex 9.

32. The system of taking controlled amounts of flood water intoareas protected Prom Sever floods by n-e!rbornnts+ e! hc an llCi in +.heIndian sub-continent since the last century and has three proven advan-tages:

l.Soi 41 -- 4-4- co-4-erl i4 s -lrasc ata te \,nitcana-. Jt. I; IV J.o u U. ., li1U JIU .L .LIJ -Jk u a siz V1'4 .L O

be held until the critical period before a harvest Twhenrains are uncertain. The crops can draw on the soilmoisture to give good yields.;

2. The silt load carried by the f:Lood i;ater is deposited ontLie e-LU,dU alL tUis inc-ease, U±L±LI\ fl.rLt y (Iti t:C%t:U

fertility following deposits of Brahmaputra River silthas been proved by FAG0 observ[erS);

3. The inflow modifies to some extent the possible higherf-lood stages outside the project area that follow con-sitruction of an embankment.

33. After construction of the embamkment the higher lands in theproject area i^ill no longer receive the limnited beneficial effects offlood water but this loss is far outweighed by the benefits to the project;as a whole through prevention of flood damage.

C. Construction Schedule

3b. The constnrction of all the wJork involved in the project isscheduled for completion within three years; the construction would bedone during t;he seven drier months of each year. Generally, no workwill be done during the five months of monsoon rainfall from May to Sep-tember.

35. Annex 1 gives the construction schedule and this shows thatthe completion of the embankment itself wviLl be done in the two workingperiods of the first/second and second/third years.

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D, Cost Estirates

36. The cost es,timates in Annex 5 are summarized below:

(in Rupees 'COO)

Local ForeignItem CGu2rrenry Currenrv Total

Eart,hT.,nrks an,,d bu il1-d J ns II 8,0l 2 -Afln 19,Q92Regulators ,3 57 3,879 10,236

21i,399 5,759 30,158Contingencies 15% ',3,f n 86!4 .24

Totcl.., f'~-ield c --- 0o O.Q 3nin A8ILU CL L j.± LU. L;UOtI LJ,VS.J2,7,2

Engineering and investigation 2,081 1,387 3,t68tAnd acquisition :3,IQ68- ___LI_

.. , )nv 0 nir rn

Overhead 5% 2,091 _ 2,091

35,9:L1 8,010 43,921interest dur:ing const;ruction atf 4,76O __ ____

tro4tal 38,6'7 A8,010 46,686at. L47o U k U l (4OUU

37. The estimalte of the cost of the earthwork has been based onmeasured quantities folloving the plotting of field surveys. To thesequantities 10 per cent aias added as a safety factor. The embankmentestimate includes the follov'ing:

Unit Cost Total CostItem Quantity Unit (Rupees) (Rs.'OC0 )

1. Earthwiork 20,939,272 cubic yard 0.80 16,7512. CompactioDn 20,939,272 cubic ;sard 0.11 2,3033. Turfing 49,627 1000 sq.ft. 12.00 596h. Fine dressing

of crest 15,613 '000 sq.ft. 2.00 31

Total 19,681

38. The unit rate of Rs. 080 per cubic yard for earthwmork is higher-than the actual 1961 rate of Rs. 0.514. The estimated costs for the regu-lators are based on quotations from reputable foreign manufacturers plus10 per cent, and inc:Lude cost of delivery and import duty.

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390 Estimated 'uiit costs of lanrd acquisition are slightly higher tharthose at present prevailing in the area. In addition to an increase of 10per cent in all embankment quantities and in regulator costs, an additiona].15 per cent contingency provision has been made on all field costs, makingthe total contingency allowance on these items 25 per cent. A 10 per centprovision has been made for engineering and investigations, and 5 per centfor overheads. Interest during construction at J4 per cent has been added.Since flood protectioin will not involve any additional capital works on thefarm, the estimates do not include any on-farm investment,

E. Financea

40. It is proposed that the credit from IDA should be US55 million,which is approximately 50 per cent of the cost of the project, Rs. 46.7million (US'9,8 million). The Government of Pakistan would relend the proceedsof the credit to the Provincial Governme:nt on the same terms and conditionSas those agreed upon between IDA and the Government of Pakistan.

41. The Provincial Government would relend the proceeds of the IDA Creditto EP.WAPDA at h per cent per annum wjith an amortization period of 25 yearsincluding a 5--year period of grace.

420 Expenditures would be scheduled approximately as follows:

(in Rupees 000)

Year Local Currency Foreign Currency Total

1 13,537 481 14l0182 5857 4; 1978623 9,282 3,524 12,806

Total 38,676 8,010 46,686

43. The main items to be purchased abroad would be steel pipes, screw-down PatRA- st1eeL shppt and stepl for rpiLnforciLng Both the materials andequipment wou]d be purchased under international bidding.

44. Disbursement for foreign exchange would be made against importdornimen.ts and the balance of the proposed credit eiould be disbursed as apercentage of the local currency expenditure.

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F. Organ 5.zation an,d 11anagement

45. The project would be executed by EP.WAPDA which is a statutoryorganization created in 1958 by the Government of East Pakistan for theco-ordinated development and utilization of the water and power resources ofthe Province. EP.WAPDA's funds are provided a) by the East Pakistan Governmenrtin the form of grants and loans, b) by sale proceeds of electricity, c) bysale proceeds of bonds issued under the Au-thority of the Provincial Government,and d) loans and foreign aid obtained with the sanction of the ProvincialGovernment, The Auth)rity's accounting system, budgetary control and auditingarrangements are on the same basis as those of the Public Works Department,but separate accounting would be maintained for the project which would besubject to internal audit by the Comptroller and Auditor General of Pakist;an.

46. The EP.IiAP])A already has responsibility for a number of large powerand water projects, including the Kaptai hydro-electric project and the GangesKobadak irrigation proiect. The Authority is alsoi-esponsible for the exten-sive coastal embankment projects in East Pakistan, in comparison with whichthe Brahmaputra Floodi Embankment is relativelv small. EP.V,APDA retains theInternational Engineering Company (IECO) as general consultants, whose duliesinclude the review and aiproval of all schemes included in the Five-Year Plan.IECO itself will not in future undertake design or supervision of individualproj.ects.

h7. Although EP .iNAPDA has a large staff and employs IECO as generalconsultants, it would be necessary f'or foreign consulting engineers to beemoloved. perhaps in association with a local firm. for design and superviLsio.,of construction of this project. The project works involve no special techni-cal difficulties. but the embankment is 13N miles long and involves excava-tion of over 20 million cubic yards of earth. It is essential that all earth-work plac.ed for the embankment shonid hp nronprlv consolidaited. The consultirgengineers would be responsible for ensuring that the wrorks were constructedto adequate standards;r their terms of referpnrre wmilrl d 'h approved bh TDA.

The earthwoTn-rk wroun di inunl re mainly hand b ohnr -apnart. f'rnm iiup nO

rollers for consolidation, and would be carried out under contracts advertised.ocall.v This tvyp rof work is already being carried out on an extensive -cale

in the coastal area, where above 120,000 laborers are seasonally employed onit. It is estimated that about 18,000 men would be employed in the dry montsf.during the construction period on the Brahmaputra project.

49. Once construction is completed, EP.WAPDA should be capable of operat--i nVt +the proj ect+ sa+i Ifactri. ITf n+ at ir +anyt +me he P"AlTrovreinclal (Gorrnynvan.F

proposed to transfer the responsibility for the operation of the project fromEP lX.APDA to ea diffrent or e at r -zati o i o a Tngn A rIDA nwl n+d fi eA i n

advance of the proposed change. Adequate measures would be taken for theproper,nn-&C mitnc of the ,nr%+s B1uilt or -econs, 4-n,c+eA ur.der the projecVt1

These measures would include continlous inspection of the embankments andprompt- repaiLr of damage A-e to eoinor other causes, -prohlbitlon of ---vapr'41~'S L ~ JX '~ LO.~'.t1 'S~ U.L J 1& 4.A '4SVL 1 FjLW '11UJ. U.L'41 '1 . 1~ L= V (1

of earth endangering the embankment and. prevention of damage to the embanr.kmertfrom r,;heeled.trafIc.... atnd VE livestock.

v0 At. present the far-mers in the area have the benefit of the agri-cultural extension services of the DepELrtment of Agriculture, operatingmainly at thana (district.) and uniVon le-vels. Wihen the em.bakrmen1t project

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is completed, the expected increase in production will be derived from farmingpatterns not radically difierent from those now being followed. EP.I!APDA isalready training its own extension officers for employment in its projects,but these mern will be needed first on irrigation projects where new farmingtechniques have to be taught. Meanwhile, the East Pakistan Government proposesto transfer some of the responsibilities of the Department of Agriculture tothe recently established Agricultural Development Corporation. Satisfactorytechnical assistance and extension servi.ces would be provided to farmers inthe project area, to enable them to take the maximum advantages from floodprotection as well as to guide them in the establishment of adequate croppingand rotation patterns; and in the adoption of improved cultural practices.

G. Operating Results

51. GrEadually increasing benefits can be expected from the second yearof construction onwards when flood damar7e is reduced, At full developmentthe benefits would Justify a flood protection charge sufficient to coveroperation andl mainterinnne rosts and to repover the investment with interest.The Provincial Government would arrange for the assessment and collection ot'charges from the hPne.fir iaries iinder thhe East Bengal Embankment and DrainaueAct which permits the recovery of operaltion and maintenance costs and of themonies invPeiPt9 in the pronect .with intereE;t within A period not exreedinp20 years.

52. The increase in net value of production per cultivated acre beforeflood protect;ion charges would be higher in fiviqnon TTT than in Di visionsI or II. FoIr the project area as a whoLe, it would be about Rs. 78 percultivatved acre, (An,nex 8) Hav,ing regard Yn+ ril +to in^crase in net valii.of production but also to the level of net value of production reached after4'1 nA nrr+ nn 4 *n 4 *. *~,n AnA (n-, h~l * h A A ha Pc 0'7 S 1r, n, + * ,.+ ~A nnr ,f ;-PO100. prox8wC.v-vIl 1- provl-ev IT1C- W1VLV, bEW P. 070 per cAt"rlated acrei

Division I, Rs. 286 in Division II, and Rs. 219 in Division III), the govern-,.ent intnd tha a4 4.form chrg sho:L be -leidhouhuteprjcmen U1Ue d LIII L LLL1LJ.VIIII ULILI rr- OIIUU.L%U LJK- LK- V kA± U' I"rijVtAV ULI~ tF

4

area. A unihorm charge of Rs. 8.5 per acre gross or Rs. 13 per acre cultivatedwo-ui be suf.i cien' 4; -oe the1- annual- opraio -ar, mantnac costs --- --- 4 of the+

project, estimated at Rs. 900,000, and to enable the monies invested in theproject to be recovered at L- per cent interest oer year ( .

- 12 -

V. Benefits and Justbification

53. The level of agricultural production and the farmers? net incomewould be increased by flood protection provided by the project. The farmersin Division I]I would obtain the largest benefits. There would be relativelyless improvement in Divisions I and II which suffer much less damagefrom flooding than does Division III.

54e Annex 7 shows the expected cropping pattern and estimated futureyields. The main change in the cropping pattern would be from broadcast aman,or mixed aus and aman, to transplanted aman. In addition to higher yieldsand greater certainty, the shorter growing season of transplanted aman wouldpermit the growing of a crop of aus on the same land before transplantingThis practice is already applied in those parts of the project area whichsuffer comparatively less damage from floods. On the basis of the presentoutlook, it is expected that the amount of land producine jute would increaseonly slightly but if market conditions warrant it, the amount of jute grownin Division III could be increased at least up to the level now prevailingin Divisions T and II,

55. After construction of the embanikment, some of the flood benefitswould be lost (see para. 33). esneciallv in the higher areas. Those areaswhich produce a third crop during the winter season w,ould be reduced andacreage devoted to pulses and oilseeds in Division III would decline.

56. Yield estimates for Division TrT are bhsed on results that arealready being obtainecl in Division II belhindl the existing embankment whereregular flood damage does not onoor- and whelre soils are irilr to thosein Division III. It should be emphasized that the estimated future levelof vieldis; t.houih higher than what. is norw h beng qnhieven in this nart of theproject area, would still be low by comparison with yields obtainable underfavorable conrlitions in East Pakistan or other countries. A yield of npraddv

of about half a ton per acre, which is the estimated 'Level of production,is low by the standards of most couni_e Though flood- protectin is anessential first step towards higher production, a satisfactory level of outputwill not be achi until irrlgato is available

57. Gradeually increasi nga -r rwrdciti rvn i.uuld be exnected from the second!year after cormencement of construction when flood damage would already bereduced. Sample surveys taken in Division II indicate that farmers readil.yresponded and made the relatively minor adjustments in cropping patternsnecessa. to -tiliz t;he f1-lo protec+in., n o newnT c s-i1l woal b -enncaed

in the project area and it is reasonable to assume that the stage of fulldevelopment+ would be *-eached by ihe fi' +h ,iv v,l+ a ker' beinnlg no fP rmnnt+r1cio

8 Th--be expec1iec ch-anes 4i the -ro-Jng -pa++ern ,old 'bring naout ny+r -r

a slight increase in cash expenses, mainly to cover the cost of additionalII,;b A 1 .- 0L n .0 ,: ;q.,L A .n A - - - -

44 - A .+nA-- A -a n

4 Annu-I1 n,,rAo a+; ntItiL CVI .. uJ. E CC:jJ.± OLL ~s.na .oU. CJ CAIC :;V CO CAICA>i VW aJ..C.C .. aIaLiA. G-%JJ VCA GV|C.I.JIAC VUDJ4.CAI

on farms of average size with that expected after completion of construction0 4. Uit jLU C 1 .J 1-~lA 4L.UIC 1 ±L 4- -d- -I- - -LI LAIIC --- 4--4J - ----J ---~. C -1iC- -in the project anne nex i3 n such farms in Wthe .ject are zre shwnin Annex 3.

- 13 -

59. The gross value of annual production would increase fromabout Rs., 1(1.5 million to approximate:Ly Rls. 136.2 million at fulldevelopment, or by about Rs. 3L.7 million (Annex 8). The net value ofthe increase in annual production before payment of flood protectioncharges wou3Ld be apT)roximately Rs. 30.7 million (Annex 8). Afterdeducting the annua]. cost of operating and maintaining the project, thenet farm benefits would be of the order of Rs. 29.8 million, Allowingfor a development period of five years after conmiencement of construction,and computing the annual net benefits over the lifetime of the project -50 years - t,he average annual return to the economy at farm prices wouldbe about 50 per cent.. These estimates are necessarily approximate butthey clearly indicat,e that the returns from the increased crop productionwould be very high and fully justify the execution of the project.

VI. Conclusions and Recommendations

60o The project would benefit a large area of land which at presentsuffers severe loss due to flooding.. I'he obiectives of the project wouldbe limited to flood protection and can be justified on this basis alone,though irrigation and drainage are expected to follow and would be essentialbefore a high level of agricultural productivity can be reached.

61. The technical aspects of the project are sound and with the assistt-anee of exnpriniind consultantsj Fp iWAFDA shomld e cnaphale of executing iteffectively.

62, The substantial economic benefits would fully justify the invest.-.ment. Flood protection charges should yield revenues sufficient to repayrthe capital investment in a period shorter than the lifetime of the project.The project w;7ould be suitable for an !DA c:redit of UST5l 0 million.

June 17, 19653.

A~NN'EX 1

BRASMAPUTRA FLOOD EMBANK5ENT PROJECT

PRESENT CROPPING, YIEIDS, PRICES ANTD VALUE OF PROWEJCTION

rr.Lu~~~~c Iot alDivision I Division II Divisioni III Total_ Divr. I Div. II Div. III VaJLue

(Cu Lt Ar 7 Acres CulClt. cree; (Culto Acres of54J,900) 56,800) 282,000) 393,700) Prod.

Acres Acres Acres Aid/ Mnd/' Mnd/ Rs/ Rs. '000of Crop % oi' Crop % of Crop a Acre Acre Acre Mnd. (Roimdedl)

Aus 25p678 47 23,936 42 1559686 5;5 205,930C) 114.2 .14.5 7.3 LI 25*875

Jute 18v591 34 16,248 28 58,637 21L 931,476 12.8 140o 8.4 25' 23,,950

BroadcastAman 482 0.8 60776 12 14j,217 140 12L,9475 1O.O 9.9 5.7 '11. 10,121

TraflBplanltedaman 30t813 56 31, 248 55 LL6,771 1L1 17130832' 314.8 16.0 6,5 l3 24,0l1o

Pulses 805 1.4 1j,21.6, 2 51, 819 1.8 5:3,84o 9.0 900 4.9 14i. 3,809

Oilseed 1,447 3 2,360 4 39,661 114 4:3,1468 1.0 4,o 309 30 5#097

Sugarcane 1,098 2 1,136, 2 5,640 2 7,874 300 300 300 2,0 4,724

Vegetables 1,098 2 1,136 2 59640 2 '7,874 50 50 50 10 3,937

Total 80,012 1146.2 814,056, 147 548,071 193 712,139 - - - - 101,P524

BRAMHMAF-UTRA FLOOD EMBfAlNXKEENT PROJECT

TYPES OF RICE GROW IN THE AREA

Theiore ae tw4o d.stinct 4grups of -rc- gro- -n the p'ro,ect areaThey are broadly classified according to the season of harvesting. Thetwo g.oups are again subdi-vided accordng to cultural charactriesticsparticularly habit of growth and length of growing season. The main grouosand lUlthe only -4uUU.ion. Iit is4 ncsy4dtif n- conne c4tio n wi; +uh

thi s project are:

1. Aus - for aut,umn harvesting

20 Aman - for winter harvesting

a) Brcadcast Aman

b) Transplanted Aman

1. Aus or Autumn Rice

A semi-dry land crop, mos-tly sown broadcast on the higher landin Miarch and April. Aus is very susceptible to flo-oding auring tne firsttwo months of growth. It is harves-ted after about 3 to 3 m,onths. Yieldsare usually rather low and subject -to serious loss if showers or monsoondeviate greatly from expectation.

2. Anan or linter Rice

a) Broadcast Aman, often called "floating rice" or "deep-waterrice" because of its ability to adjust its length of stem to the depth offlooding. Sown broadcast on lands sub,ject to deep flooding whilst the landis still dry in M1arch or April. Th-e seed is germinated by pre-monsoonalshowers and plants must becone well established before the flooding. As theflood waters rise, the plants grow alorng vith the rising water, the stemsattaining lengths up to 10-12 feet. Rapidly rising flood water and swriftcurrents, especially during the earlier stages of broadcast aman growth,cause damage. The yield of this group is inherently low and produces poorlyunder normal water levels. The crop is harvested in November and December.

b) Transplanted Anan. This group contains the greatest number ofthe best varieties. The seed is sown in nurseries and after 40 to 50 daysthe seedlings are transplanted into pucddled fields. Inundation to a depthof more than one foot prevents successf'ul transplanting. At present,throughout the project area, transplanlting has to be delayed until Septem-ber/October after flood danger has passed. Given flood protection, a longergrowing period and higher yields can be obtained by transplanting in Julyand August. The crop is period-fixed, reaches the heading stage in October,and is harvested in November/December.

ANNEX 3

BRAXMAPUTRA FLOOD DBANMENT PROJECT

Approximate Farm Budgets "Before" and "After" Projectfor Farms- 4with 5 Clt4ivatted Acres

C R 0 P V A L U E S- D:______biv.s.ons I & II---------------ivision III-

Bei'ore Project After P-13 Develop. Before Project After Full Develcp.Are=a 'alo-ua Area Wz 0- ue ^w ,w -a S5

C r o p (acres) (Rs) (acres) (Rs) (acres) (Rs) (acres) (Rs)

Aus 2,73 543 2.90 589 3.19 326 2.90 487Jute 1.,97 630 2.03 710 1.22 255 1.45 435Broadcast Aman 0.05 7 nil nil 2.32 185 0.87 96Transplanted Aman 3.25 673 3.48 721 2.38 217 3.19 626Pulses 0.08 10 0.17 21 L.04 71 0. 6 "7

Oilseeds 0,17 21 o.46 54 0.81 96 o.69 84S,g,ar Cane 0.12 72 0MP 72 0.12 72 0.12 72Vegetables 0.12 60 0.12 60 0.12 60 0.12 60

Total 8.,49 2,016 9.28 2,227 11.20 1,282 9.80 1,907

C A S H E X P E N S E S(Rupees)

---------Divisions I & II----------- -------- Division III------------I t e m Before Project After Ful.11 Develop. Before Project After Full Develop.

Seed 77 84 85 83Man 1Abo r Hl-sd)u U..) 44°, 373 1Animal Labor (Hired) 31 35 30 40Replacement &

MaintenanoeOwned Bullomcs 40 40 40 40

Replacement &Maintenance Tools& Equipment 15 i5 15 15

Taxes 37 37l 37 37

Total (Before 585 651 580 637Charges)

Proposed Charges -- 75 -- 75

Total (Incl. 585 726 580 712ChaSrges")

Net Income 1,431 1,501 702 1,195

S-UiOARY: Increase in gross income: Rs 211 Rs 625Incresase in net income:a) Beforee charges .Ra. 'X5 1. 5 t eb) 1Jf,tJo charges Rs 70 Rs 493

b) After charges Rs 70 Rs 493

AkEx 4

EAST PAKIISTAN

I3RAHMAPUTRA FLOOD EMBANKMENT PROJECTCONSTRUCTION SCHEDULE

PFP'RSr YFA ' SE-COND YEAR' THIR D YE4AR _

F|Al VF|,JIA S SON VD J|F MA fM I9ITJh A LS ) J MKKIA SA DI KALINIATO BELKA---

De,lai/ /r,ves'i9gation and… --|u, Svey…- - -- …-PIrocurcemen/ of Equipment

; BU;/'n9S _ Ma_LLe /

Bui/dirpgs --

| r bbankme n, 1 II I 1 I I L,LI

| ___________ -P! T1r1 1r1 TTT tI I 1IIIIVI1 ItTIj X I

I .U' ,6EL/rA TO /-JSLC'AHAR/ I IIi ii ii i l lii -

Detail rvesfgfo an

_____ _____ -t t n c -xl--.-"-------- 1 |H4<-

Pr-ocuremen t of Equ.pment| and Materials ni_1

B u i/ din -gs

I Ebank7 krn| +i+--hi-l-

R iegulators ; <X

JRULfoYR' TO kPASAG.AR F.---

De'ail )nvafl i_-afion anj- .~Surveq __ ZyU2L- 1 L Pocur'emanen OfFEquiprTiCent

JUNE I962 I 6RD- 10)14

ANNEX 5

BRAHOAPUTRA FLOOD EMBANKMENT PROJECT

COST ESTIMATE(In Rupees '000)

Divisivn I Dilvision II Divisizn III Total ProjectLocal Foreign Tot.l

Tot--' Total Tvtal Currence CurrencirRs, Rs. Rs, Rso RR0 Rse

Embankanent 29072 4,313 13,297 17,802 1,1880 19,682

Cost of' Buildings 67 67 106 240 - 2 4o

Reigulators -- 3133 7l103 6,357 3,879 10,'36

Sub.-Total1 I 2,139 79513 20,506 24399 5j,759 30,158

15% Contingency 321 1,127 3,075 3,660 864 4,24

Sub'-Total II 2,460 89640 23,582 28,059 6,623 3h,682

10g Investigation 246 864 2,358 2,081 1,387 32468

Sub.-TotaLl TII 2,706 9,50o4 25,940 30C,140 8,010 385150

C.st of Land -602_ 512 2,566 3,680 -3 ,S80

Sub--Total IV 3,308 10c016 28,506 33,820 8,o10 h1,830

5% Overhead1 165 501 1,425 2,091 - 2,091

Sub-.Total V 39473 10o,57 29,931 35,911 8 S'010 433921

Interest During 2,765 _ 2;765Constructicvn 2 _

Grand T<>ta1 389676 8,010 h6,f686

ANNEx 6

BRAHKhPUTRA FLOOD E2D3ANTI&IEI IT PROJECT

Financia]. Operating Results at Full Development

Revenues Rs. 1000

Flood protection charges(593,500 acres at Rs.8.5 per acre) 5,o45

Operating Costs

OperatiLon and rnaintenance 900

Balance hbefore interest and HAnreniation h,lLS

T.n-rPr iqti-Ai) over 50 yrpers 934

Surplus after depreciation 3,211

Ass-ng- 4that +e t++t,l ba1-lnc -efore intre '-mA

depreciation would be used for debt; service, the pay-back period at1. per cent- int-erest- would bee approx;,Xa y16, years.

ANq -

BRAJMAPUTRI FiLOOI) IBANKMlNT F'ROJECT

FUT_RTE CRPING, YIEL]3S, PRICES AND VAILE OF PRODUriClriff

lrbae Yields Price TotalDivis,4iT 4 Y n..L4 TTifL Dnv.is itn TTI1 T Divt Dirv. 'TT DiT v L IIIVaLu

TMrt, rem 'iCit Acs T`Uult. Acreas -t. -FCei of5400900) 5658,oX) 282,000) 393,700) Prod.,

Acres Acres ALcres Mnd/! Mnd/ M/d/ R R/ s t00of Crop : of Crop % of Crop % Acre Acre Acre lnd. (Rounded)

Aus1 217,450 5-0 28,4kOO 50 lla,ooo 50 196,850 14.5 14e5 12 o0 14 350216

Jute 19,215 35 1998180 35 70,500 25 109,595 ili0 14.o 12.0 25 34J,833

BroadcastiAua Nil. Ni4 1,704 3 423,300 15 44i,004 Nil 10.0 8.0 1k4 1k,976

TransplanW-Amain 32,940 60 34,0130 60 155,o100 55 222,120 14k8 16.0 1h.O 1k4 44#859

Euulses 1,647 3 1,704 3 22,560 8 25,911 9.0 900 7.5 14 2,791

Cilseed 4,392 8 45J44 8 33,s840 12 42,776 4.o 4.o 4ko0 30 5,133

'Sugarcane 1,098 2 1,1:36 2 5,61jo 2 7,874 300 300 300 200 4p724

VFegetableis 1,098 2 1,136 2 5,,6bo 2 7s,874 50 50 50 10 3,937

Total 8?7840 160 9295134 163 416,58o 169 657,004 - - - - 136,279… ___- __

ANNEX 8

BRAMDA 1'APDfA FTLOO t. oT *. .TTT PPRO.T1.flT

STfM.Aiv,` OF rLPrO1 C Q. ?LTPrP IT TTM OFV Drnriiw'TrTTOh\P p-T , \qTr7P PrnfTlhP 1 CE T

Per Acre Cultivated Totalflr,ss Varnaers! Ne Gros Fames Ne

Va:Lue Expenses Value Value Expenses ValueBefore BieforeFlood Flood

Pro'bection rloe ueU -Voll

Charges Charges

I)ivision I

Before Project 34L6 101 245 18.9 5.4 1345

After Project 384 112 272 21.0 6.1 14.9

Increase 33 11 27 2.1 0.7 1.4

Division I1

Before Project 355 101 25b 20.2 5.8 iL4

After Project 393 112 286 22.6 6.4 1l6.2

Increase 43 11 32 2.4 o.6 1.8

Division ITT

Before Project 221 100 121 62.4 28.2 34.2

After Project 329 110 219 92.6 31.0 61L6

Increase 108 10 98 30,2 2.8 27.4

Total Proiect

Before Project 258 100 1.58 101.5 39.4 62.1

After Project 346 110 236 136.2 43.4 9208

Increase 88 10 78 34.7 4.0 .30.7

AfXTNEX 9

BRAFI4NA1 !PUTRA FLOOD Ei' 4BANKMENT PROJECT

DESCRIPTION OF FROPOSED "JWORKS

The heigh+ of thXe embar.kqr.ent above the ground wo.llr irease fromthe north end at Kaunia to the middle of D:ivision III at Sirajganj; it wouldthen 1Perel off i 4 )n the lnowr part -r Tn;-; I4I TTT T ; ,r;c;on T +ho ho; rhtwould vary from 5 feet to 15 feet anid average 11.60 feet. In Division II,which includes the length of embankiment. bu-lt in Q it `7 var from8 feet to 17 feet and average 12.80 feet. At the upper end of Division III,bet-een Phulchari and Sira jganJ, tht g-.eatest ovebank flooding tc kes placeand here the height of the embankment generally would vary between 10 feetanl 20 feet, averaging abouL i14 feetr. In tne iower part of Division III(between Sirajganj and Hurasagar, at it.s southern extremity) it would varygenerally between 7 feet and 14 feet, averaging about 9 feet. The averageheight throughout Division III would be 11 feet.

Using the limited hydraulic clata. available, calculations have beenmade of the height of floods of one hundred years! incidence along the 135miles length of the embankment. These heights have been plotted on thelongitudinal sections to give the design water level^. The calculationsare based on the records for 3 stations: Kaunia, on the Teesta River at theRailway Bridge, for which records are available from 1945 onwards; Bahadurabad,on the Brahmaputra River below its confluence with the Teesta, with recordsfrom 1949 onw.ards; and Sirajganj, on thie Prahmaputra River, with records from1948 onwards. A safety factor has been introduced by making the designed toplevels of the embankment 5 feet higher than the "design water level4.

The higher flood stages which may be caused outside the project.due to the embankment have been the subject of a hydraulic analysis based. on1960 flood records; but the data are not adequate to allow a precise estimateto be made of the li-kely increase in f'Lood level. 1960 flood records inc.icatethat increase in river stage level due to the embankment might be of theorder of magnitude of 0.1 foot at Sirajganj. With minor river floods, thechanges due to the embankment are expected to be negligible; with major f'loods,river stages are not. likely to be raised by more than 12 inches at most,which is not excessive for the terrain, and flood damage to property andcrops for tihe Brahmaputra and Teesta riverine lands outside the project areawill not be significantly increased followiing construction of the embankmernt.

ACter the emiban.kment is constructed, the drainage of the projectarea will be effected by using the existing channels of the streams behindthe embankrment. In Division I, where flood damage does not occur every yearexceDt in pLaces adiacent to two small spill channels, the embankment wouldnot be provided with means of permitting intake of flood water or dischargeof internal drainage water. The floods would be totally excluded, andinternal drainage water will be conveyed in the existing channels to DivisionII. The embankment already constructed in 1952 from Belka to Phulchari grivespartial protection from flooding to the Division II area. Openings in thisembankment were Ieft where t.he river M nm anc1 Sarni enter the Prahmanut;raand, during high stages of the BraFmnaputra, flood waters frequently back up

A ?Mhl'Y 0

page 2

nILno tihese opn[n, causing dJ-uamage Lo c: roi 6. It is- LA) tocnstruct.

regulators at these two openings; these regulators would pass out internaldrainage wauer from Divisions I and II and they would be gated to preventingress of fLood water from the Brahmaputra. The existing internal drainagechanne]s wou-ld therefore function much as before but without having to dealperiodically with flood water from the Treesta and Brahmaputra. The SaraiRiver regulator would have a discharge capacity of 1,000 C.I.S. and the ManasRiver regulator 8,000 c.f.s., a capacit-y which is based on flow records ofthe Ghagat River (a large tributary of the M4anas) and a drainage area relation-ship. An adequate study of the probable internal drainage discharges for theSarai and Manas Rivers is impossible as the rainfall records and river stagedata for duration and intensity of floodis are deficient for the purpose.The designed regulator capacities are based on a projection of the flowcapacities of the channels of the internal river system. This method shouldgive a fair approximate estimate of the discharge capacities required for theregulators but it has been considered advisable to increase the estimated costof the two structures by 50 per cent so that increased discharge capacitycould be provided. Over some 6,000 acres behind the proposed Manas regulatorsinternal drain1age water, which would be liable to be impounded during highstages in the Brahmaputra, would be diverted through the old channels ofthe Manas River.

In Division III internal drainage would be directed in the existingchannels to the south, where it would be discharged without control into theGanges. Backing up of floocl water during high stages of the Gnges wouldaffect a largre area of low land outside the project area but the severity offlooding there would not be significant:Ly increased by construction of theembankment. At intervals alorg the embankment, six regulators or culvertsare to be provided for bringing flood water from the Brahmaputra into thepro.iect area., These culverts have a cormbined intake capacity of 18,600 c.f.s.and they will be sited where natural inflow channels already exist. Thetotal inflo- is related to thle size and capacity of the internal drainagechannels and their ability to deal with the estimated interna:l drainage flow,plus planned flood water intake. It is not; expected that the culverts willhave difficult design or construction problems. The design is standard and7 feet and 10 feet diameter steel pipes will be used.

AUNIA

-, D.ision I { 0||* t ' | ' yj \:r'?

, r PAKISrAN

DiyJision t I

;-

''% j aAX -d -:j/

S W X~~~~~II,

N.;

A ~~~. Locahf ,.n )

[ w s n ZI -4 t < NS BRAHMAPUTRA FLOOD

$ -¢EMBANKMENT PR 'JECT

j j 4t ~MAHIMAGA >

|

0 5 10

2- I -2

,. 9J1L

1 .g l(

*i

Div isio n

*, >

IL

V-v~~~~~.

3 -<

A X1! 1

v /X0XI

RA t .LL.J '

BRANMAPATRA Fi v i s i o r)

. ..........~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~ .

Sp I